Department of Chemistry, Stanford University, 337 Campus Drive, Stanford, California 94305, USA.
J Am Chem Soc. 2012 Feb 1;134(4):1986-9. doi: 10.1021/ja2108799. Epub 2012 Jan 20.
The importance of tin oxide (SnO(x)) to the efficiency of CO(2) reduction on Sn was evaluated by comparing the activity of Sn electrodes that had been subjected to different pre-electrolysis treatments. In aqueous NaHCO(3) solution saturated with CO(2), a Sn electrode with a native SnO(x) layer exhibited potential-dependent CO(2) reduction activity consistent with previously reported activity. In contrast, an electrode etched to expose fresh Sn(0) surface exhibited higher overall current densities but almost exclusive H(2) evolution over the entire 0.5 V range of potentials examined. Subsequently, a thin-film catalyst was prepared by simultaneous electrodeposition of Sn(0) and SnO(x) on a Ti electrode. This catalyst exhibited up to 8-fold higher partial current density and 4-fold higher faradaic efficiency for CO(2) reduction than a Sn electrode with a native SnO(x) layer. Our results implicate the participation of SnO(x) in the CO(2) reduction pathway on Sn electrodes and suggest that metal/metal oxide composite materials are promising catalysts for sustainable fuel synthesis.
通过比较经过不同预电解处理的 Sn 电极的活性，评估了氧化锡（SnO(x)）对 Sn 上 CO2 还原效率的重要性。在 CO2 饱和的水性 NaHCO3 溶液中，具有天然 SnO(x)层的 Sn 电极表现出与先前报道的活性一致的电位依赖性 CO2 还原活性。相比之下，蚀刻以暴露新鲜 Sn(0)表面的电极在整个 0.5 V 范围内表现出更高的总电流密度，但几乎完全是 H2 的析出。随后，通过在 Ti 电极上同时电沉积 Sn(0)和 SnO(x)制备了薄膜催化剂。与具有天然 SnO(x)层的 Sn 电极相比，该催化剂对 CO2 还原的部分电流密度提高了 8 倍，法拉第效率提高了 4 倍。我们的结果表明 SnO(x)参与了 Sn 电极上的 CO2 还原途径，并表明金属/金属氧化物复合材料是可持续燃料合成的有前途的催化剂。
